A known transmitter/receiver for such communication is shown in FIG. 1.
In a manner known per se, the transmitter comprises an amplifier 1 having an input terminal 4 for signals to be transmitted, an output stage 3 with output terminals 5, 6 coupled via termination resistors 7, 8 to a transmission medium, e.g. a transmission line, represented by a load 11, and a negative feedback circuit 2 connected with its input terminals to the output terminals 5, 6 of the output stage 3 and with its output terminal to the input terminal 4 of the amplifier 1, where the output signal of the feedback circuit 2 sets the transmit gain.
The receiver 9 is connected with input terminals 12, 13 across the load 11, and is provided with an output 10 for outputting received signals.
In the transmitter/receiver in FIG. 1, when the termination resistors 7, 8 have the same combined resistance as the load 11, half of the transmitted and half of the received signals are extracted by measuring the signal across the termination resistors 7, 8.